JP2022114397A - Object detection device, transmission device, and electric power transmission system - Google Patents

Abstract

To provide an object detection device, a transmission device, and an electric power transmission system for detecting an object with high accuracy during wireless power transmission.SOLUTION: An object detection device 100 includes: a sensor module 110 having a sensor 120 and a control unit 130 that controls the sensor 120 and generates output information based on a signal outputted by the sensor 120; and a detection unit 190 that determines the presence or absence of an object based on the output information. The detection unit 190 executes a reference object detection process of comparing the output information with predetermined reference information to detect a reference object present in a predetermined position within a detection range, and executes a correction process to correct at least one of the output information and a parameter for the sensor 120 based on reference object information, which is information indicating the reference object from the output information, and the reference information, when the reference object is detected.SELECTED DRAWING: Figure 5

Description

The present disclosure relates to object detection devices, power transmission devices, and power transmission systems.

Wireless power transmission technology for wirelessly transmitting power is attracting attention. Wireless power transmission technology can wirelessly transmit power from a power transmission device to a power reception device, so it is expected to be applied to various products such as transportation equipment such as trains and electric vehicles, home appliances, wireless communication equipment, and toys. Wireless power transmission technology uses a power transmitting coil and a power receiving coil that are coupled by magnetic flux to transmit power.

By the way, if an object such as a living body or a piece of metal exists in the vicinity of the power transmission coil, various problems may occur. For example, if a living body exists in the vicinity of the power transmission coil, the living body may be exposed to the electromagnetic field generated during power transmission, causing health problems for the living body. Therefore, an object detection device that appropriately detects an object existing near the power transmission coil is desired.

US Pat. No. 6,200,000 describes an apparatus for detecting objects in a detection area proximate to a wireless power transfer system for charging electric vehicles. Based on radar data received from a radar transceiver, the apparatus described in US Pat. No. 6,200,000 determines at least one of the distance to an object, the velocity of the object, the position of the object, the direction of the object, and the size of the object.

Patent No. 6636510

However, the device described in Patent Document 1 does not take into account changes in the environment such as temperature, humidity, amount of light, and wind speed, deterioration of the device over time, and the like. For this reason, with the apparatus described in Patent Document 1, even if the presence of the object is the same, if the environment, the age of the apparatus, etc. are different, there is a possibility that the determination result will be different. In other words, it is considered difficult for the apparatus described in Patent Document 1 to accurately detect an object. Therefore, there is a demand for a technique for accurately detecting an object during wireless power transmission.

The present disclosure has been made in view of the above problems, and aims to accurately detect an object during wireless power transmission.

In order to solve the above problems, an object detection device according to an embodiment of the present disclosure includes:
An object detection device that detects an object existing in a detection range,
a sensor module having a sensor and a control unit that controls the sensor and generates output information based on a signal output by the sensor;
a detection unit that determines the presence or absence of the object based on the output information,
The detection unit performs a reference object detection process of comparing the output information with predetermined reference information to detect a reference object existing at a predetermined position within the detection range, If detected, a correction process is performed to correct at least one of the output information and the parameter for the sensor based on the reference information indicating the reference object in the output information and the reference information. do.

According to the above configuration, it is possible to accurately detect an object during wireless power transmission.

Schematic configuration diagram of a power transmission system according to Embodiment 1 1 is a perspective view of a power transmitting coil unit and a power receiving coil unit according to Embodiment 1; Layout of sensor modules according to Embodiment 1 FIG. 2 is a top view of the sensor module according to Embodiment 1; Configuration diagram of an object detection device according to Embodiment 1 Functional configuration diagram of the sensor module according to the first embodiment Functional configuration diagram of a detection unit according to Embodiment 1 Diagram showing reference information Diagram showing output information 4 is a flowchart showing object detection processing executed by the object detection device according to Embodiment 1; Flowchart showing update processing shown in FIG. Layout of sensor modules according to Embodiment 2 Layout of sensor modules according to Embodiment 3 13 is a flowchart showing update processing executed by the object detection device according to the fourth embodiment;

A power transmission system according to an embodiment of the technology according to the present disclosure will be described below with reference to the drawings. In addition, in the following embodiment, the same code|symbol is attached|subjected to the same component. Also, the size ratios and shapes of the constituent elements shown in each drawing are not necessarily the same as in the actual implementation.

(Embodiment 1)
The power transmission system according to the present embodiment can be used to charge secondary batteries of various devices such as EVs (Electric Vehicles), mobile devices such as smartphones, and industrial devices. A case where the power transmission system charges an EV storage battery will be exemplified below.

FIG. 1 is a diagram showing a schematic configuration of a power transmission system 1000 used for charging a storage battery 500 provided in an electric vehicle 700. As shown in FIG. The electric vehicle 700 runs using a motor driven by electric power charged in a storage battery 500 such as a lithium ion battery or a lead storage battery as a power source. Electric vehicle 700 is an example of a mobile object.

As shown in FIG. 1, the power transmission system 1000 is a system that wirelessly transmits power from a power transmission device 200 to a power reception device 300 by magnetic coupling. The power transmission system 1000 includes a power transmission device 200 that wirelessly transmits power from an AC or DC commercial power supply 400 to an electric vehicle 700, and a power reception device 300 that receives the power transmitted by the power transmission device 200 and charges a storage battery 500. . In the following description, commercial power supply 400 is an AC power supply.

The power transmitting device 200 is a device that wirelessly transmits power to the power receiving device 300 by magnetic coupling. The power transmission device 200 includes an object detection device 100 that detects an object, a power transmission coil unit 210 that transmits AC power to the electric vehicle 700, and a power supply device 220 that supplies AC power to the power transmission coil unit 210. A detailed description of the object detection device 100 will be given later.

FIG. 2 shows main parts of power transmitting coil unit 210 and main parts of power receiving coil unit 310 . As shown in FIG. 2 , the power transmission coil unit 210 is supplied with AC power from a power supply device 220, and has a power transmission coil 211 that induces an alternating magnetic flux Φ. and a magnetic plate 212 for suppressing. The power transmission coil 211 is configured by spirally winding a conductive wire around a coil axis 213 on a magnetic plate 212 . The power transmission coil 211 and the capacitors provided at both ends of the power transmission coil 211 constitute a resonance circuit, and an alternating magnetic flux Φ is induced by an alternating current flowing along with the application of an alternating voltage. In FIG. 2, the vertically upward axis is the Z-axis, the axis orthogonal to the Z-axis is the X-axis, and the axis orthogonal to the Z-axis and the X-axis is the Y-axis.

The magnetic plate 212 has a plate shape with a hole in the center and is made of a magnetic material. The magnetic plate 212 is, for example, a plate-like member made of ferrite, which is a composite oxide of iron oxide and metal. The magnetic plate 212 may be composed of an assembly of a plurality of individual pieces of magnetic material, and the plurality of individual pieces of magnetic material are arranged in a frame shape and formed to have an opening in the central portion. may

The power supply device 220 includes a power factor correction circuit that improves the power factor of the commercial AC power supplied by the commercial power source 400 and an inverter circuit that generates the AC power to be supplied to the power transmission coil 211 . The power factor correction circuit rectifies and boosts AC power generated by commercial power supply 400, and converts it into DC power having a predetermined voltage value. The inverter circuit converts DC power generated by power conversion by the power factor correction circuit into AC power having a predetermined frequency. Power transmission device 200 is fixed, for example, to the floor of a parking lot.

The power receiving device 300 is a device that wirelessly receives power from the power transmitting device 200 by magnetic coupling. The power receiving device 300 includes a power receiving coil unit 310 that receives the AC power transmitted by the power transmitting device 200, and a rectifier circuit 320 that converts the AC power supplied from the power receiving coil unit 310 into DC power and supplies the DC power to the storage battery 500. Prepare.

As shown in FIG. 2, the power receiving coil unit 310 includes a power receiving coil 311 that induces an electromotive force in response to a change in the alternating magnetic flux Φ induced by the power transmitting coil 211, and a magnetic force generated by the power receiving coil 311 that passes through the magnetic force. and a magnetic plate 312 that suppresses loss. Power receiving coil 311 is configured by winding a conductive wire in a spiral shape around coil axis 313 on magnetic plate 312 . Power receiving coil 311 and capacitors provided at both ends of power receiving coil 311 form a resonance circuit.

Power receiving coil 311 faces power transmitting coil 211 while electric vehicle 700 is stopped at a preset position. When the power transmission coil 211 receives power from the power supply device 220 and induces an alternating magnetic flux Φ, the alternating magnetic flux Φ interlinks with the power receiving coil 311 , thereby inducing an induced electromotive force in the power receiving coil 311 .

The magnetic plate 312 is a plate-like member with a hole in the center and is made of a magnetic material. The magnetic plate 312 is, for example, a plate-like member made of ferrite, which is a composite oxide of iron oxide and metal. The magnetic plate 312 may be composed of an assembly of a plurality of individual pieces of magnetic material, and the plurality of individual pieces of magnetic material are arranged in a frame shape and formed to have an opening in the central portion. may

Rectifier circuit 320 rectifies the electromotive force induced in power receiving coil 311 to generate DC power. The DC power generated by the rectifier circuit 320 is supplied to the storage battery 500 . Power receiving device 300 may include a charging circuit between rectifier circuit 320 and storage battery 500 that converts the DC power supplied from rectifier circuit 320 into DC power suitable for charging storage battery 500. good. The power receiving device 300 is fixed to the chassis of the electric vehicle 700, for example.

The object detection device 100 is a device that detects an object existing within a detection range. A detection range is a range in which an object can be detected. The detection range is an area near power transmitting coil unit 210 and power receiving coil unit 310 . Objects detected by the object detection apparatus 100 are mainly considered to be a living body and a piece of metal. The living body may be a human body or an animal body such as a dog or a cat.

If a living body is present in the detection range during power transmission, the living body will be exposed to the electromagnetic field and may cause health problems for the living body. Moreover, if a metal piece is present in the detection range during power transmission, the metal piece may adversely affect power transmission or generate heat. Therefore, the object detection apparatus 100 detects an object existing within the detection range and notifies the user that the object has been detected. The user can receive this notification and keep the object away from the detection range.

In this embodiment, object detection device 100 includes a plurality of sensor modules 110 . Specifically, as shown in FIG. 3, object detection device 100 includes four sensor modules 110: sensor module 110A, sensor module 110B, sensor module 110C, and sensor module 110D. Sensor module 110 is a general term for sensor module 110A, sensor module 110B, sensor module 110C, and sensor module 110D. The configurations and functions of the four sensor modules 110 are basically the same.

The sensor module 110 is a unit in which parts used for object detection are housed in one housing. Specifically, as shown in FIG. 4, the sensor module 110 includes a sensor 120 that detects an object, a housing 160 that houses the sensor 120 and a detection board 170, and a detection module connected to the sensor 120 by a cable 180. and a substrate 170 . In FIG. 4, the illustration of the ceiling portion of the housing 160 is omitted for easy understanding. 4 is a top view of the sensor module 110 with the ceiling portion of the housing 160 removed.

The sensor 120 is a sensor that detects an object existing within a detection range. As the sensor 120, various sensors such as a sensor that detects reflected waves of sound waves or electromagnetic waves, a sensor that detects electromagnetic waves, and the like can be employed. For example, as the sensor 120, an ultrasonic sensor, a millimeter wave sensor, an X band sensor, an infrared sensor, or a visible light sensor can be used. In this embodiment, the sensor 120 is an ultrasonic sensor that emits ultrasonic waves with a transmitter and receives the reflected waves with a receiver. Hereinafter, the ultrasonic waves emitted by the transmitter will be referred to as transmission waves as appropriate.

The sensor 120 includes a piezoelectric element and a housing that houses the piezoelectric element. Sensor 120 performs sensing according to control by control unit 130 . The sensor 120 applies the voltage pulse supplied from the control unit 130 to the piezoelectric element and emits ultrasonic waves from the piezoelectric element. The sensor 120 also supplies the control unit 130 with a voltage signal indicating the voltage generated in the piezoelectric element by the reflected wave.

Housing 160 houses sensor 120 and detection board 170 . The housing 160 is, for example, a box-shaped member having an opening 161 at a position facing the sensor 120 . Housing 160 serves as a reference for other sensor modules 110 . The reference object corrects at least one of the parameters for the sensor 120 and the output information based on the signal output by the sensor 120 so that the object can be detected appropriately even if the environment, deterioration state, etc. of the sensor 120 change. used for The environment of the sensor 120 includes temperature, humidity, amount of light, wind speed, etc. around the sensor 120 . Note that the deterioration state of the sensor 120 depends on, for example, the years of use of the sensor 120 .

Here, even if the presence state of the object is the same, if the environment of the sensor 120 is different, there is a possibility that the signal output by the sensor 120 will be different, and the output information based on this signal may be different. be. For example, if the sensor 120 is an ultrasonic sensor using a piezoelectric element, the resonance frequency is determined by the structure of the ultrasonic sensor. When the temperature changes and the ultrasonic sensor expands or contracts, the resonant frequency changes, causing a difference between the signal output by the sensor 120 and the output information based on this signal. Similarly, even if the existence state of the object is the same, if the deterioration state of the sensor 120 is different, there is a possibility that the signal output by the sensor 120 and the output information based on this signal will be different. Therefore, the sensor module 110 detects the housing 160 of the other sensor module 110 as a reference so that a change in the environment or deterioration state of the sensor 120 does not cause a difference in the detection result of the object.

The reference object is preferably an object that remains stationary while the transmitting coil unit 210 transmits power. The reference object is preferably part of an object that constitutes power transmission device 200 . In the present embodiment, the reference object is part of an object that constitutes object detection device 100 included in power transmission device 200 . The housing 160, which is the reference object, is preferably made of a material that is easily detected by the other sensors 120. FIG. The housing 160 is made of metal, for example.

The plurality of sensor modules 110 are arranged such that the detection range of the sensor 120 of each sensor module 110 includes at least part of at least one other sensor module 110 . According to such a configuration, at least part of at least one other sensor module 110 that exists within the detection range of the sensor 120 of each sensor module 110 can be used as a reference.

Specifically, as shown in FIG. 3 , the multiple sensor modules 110 are configured such that the detection range 119 of each sensor 120 includes the housing 160 of the other sensor 120 . Disposed around body 214 . In the example shown in FIG. 3, the detection range 119A of the sensor 120 included in the sensor module 110A includes the housing 160B of the sensor 120 included in the sensor module 110B. Further, the detection range 119B of the sensor 120 included in the sensor module 110B includes the housing 160C of the sensor 120 included in the sensor module 110C.

A detection range 119C of the sensor 120 included in the sensor module 110C includes the housing 160D of the sensor 120 included in the sensor module 110D. A detection range 119D of the sensor 120 included in the sensor module 110D includes the housing 160A of the sensor 120 included in the sensor module 110A. The detection range 119 is a general term for the detection range 119A, the detection range 119B, the detection range 119C, and the detection range 119D. Further, the housing 160 is a general term for housing 160A, housing 160B, housing 160C, and housing 160D.

The detection board 170 is a board on which components for executing various processes associated with object detection are mounted. The detection board 170 includes a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), an RTC (Real Time Clock), an A/D (Analog/Digital) converter, a flash memory, and a communication interface. etc. will be implemented. This communication interface, for example, USB (Universal Serial Bus, registered trademark), known wired communication standards such as Thunderbolt (registered trademark), or Wi-Fi (registered trademark), Bluetooth (registered trademark), LTE (Long Term Evolution), 4G (4th Generation), 5G (5th Generation), and other known wireless communication standards. These components mounted on the detection board 170 implement a control unit 130, a storage unit 140, and a communication unit 150, which will be described later.

Next, the configuration of the object detection device 100 will be described with reference to FIG. The object detection device 100 includes multiple sensor modules 110 and a detection unit 190 . Note that only one sensor module 110 is shown in FIG. Sensor module 110 includes sensor 120 , control unit 130 , storage unit 140 , and communication unit 150 . The detection unit 190 includes a control unit 191 , a storage unit 192 , a first communication unit 193 and a second communication unit 194 . The detector 190 is provided outside the sensor module 110 . For example, the detection unit 190 is provided inside the housing of the power transmission coil unit 210 or the power supply device 220 .

The control unit 130 controls the operation of the sensor module 110 as a whole. Control unit 130 controls sensor 120 according to the operation program stored in storage unit 140 and generates output information based on the signal output from sensor 120 . The control unit 130 includes, for example, a CPU, ROM, RAM, RTC, A/D converter, and the like.

The storage unit 140 stores operation programs and data used by the control unit 130 to execute various processes. For example, storage unit 140 stores parameters for sensor 120 . Various parameters are conceivable as parameters. In this embodiment, the amplitude of the transmission wave emitted by the sensor 120 and the frequency of the transmission wave emitted by the sensor 120 are used as parameters. Note that the amplitude of the transmission wave is also referred to as the strength of the transmission wave or the magnitude of the transmission wave. Note that, in the present embodiment, parameter values are simply referred to as parameters as appropriate. The storage unit 140 also stores data generated or acquired by the control unit 130 executing various processes. For example, the storage unit 140 stores output information acquired by the control unit 130 . Storage unit 140 includes, for example, a flash memory.

The communication unit 150 is a communication interface for communicating with the detection unit 190 . The communication unit 150 has a communication interface conforming to a known wired communication standard or a communication interface conforming to a known wireless communication standard.

The control unit 191 controls the operation of the detection unit 190 as a whole. The control unit 191 acquires output information from the sensor 120 according to the operation program stored in the storage unit 192, and detects an object based on the output information. The control unit 191 includes, for example, a CPU, ROM, RAM, RTC, A/D converter, and the like.

The storage unit 192 stores operation programs and data used by the control unit 191 to execute various processes. For example, storage unit 192 stores parameters for sensor 120 . The storage unit 192 also stores reference information. The reference information is output information acquired from the signal output by the sensor 120 when the reference object is detected in the reference environment and the reference deterioration state. The storage unit 192 also stores data generated or acquired by the control unit 191 executing various processes. For example, the storage unit 192 stores the output information acquired by the control unit 191, the correction coefficient obtained from the reference object information and the reference information, and the correction amount obtained from the reference object information and the reference information. The storage unit 192 has, for example, a flash memory.

The first communication section 193 is a communication interface for communicating with the sensor module 110 . The first communication unit 193 has a communication interface conforming to a known wired communication standard or a communication interface conforming to a known wireless communication standard. The second communication unit 194 is a communication interface for communicating with the power transmission coil unit 210, the power supply device 220, an external terminal device (not shown), and the like. The second communication unit 194 has a communication interface conforming to a known wired communication standard or a communication interface conforming to a known wireless communication standard.

Next, the functions of the sensor module 110 will be described with reference to FIG. The sensor module 110 functionally includes a drive unit 131 , an output information acquisition unit 132 , and an output information transmission unit 133 . The drive unit 131 , the output information acquisition unit 132 and the output information transmission unit 133 are implemented by the functions of the control unit 130 . That is, the drive unit 131, the output information acquisition unit 132, and the output information transmission unit 133 are configured by a computer having a CPU, a ROM, a RAM, an RTC, an A/D converter, etc., and an operation program stored in a ROM or flash memory. It is realized by executing

Drive unit 131 drives sensor 120 under the control of detection unit 190 . Specifically, the drive unit 131 supplies the sensor 120 with a voltage pulse for causing the sensor 120 to transmit a transmission wave having the amplitude and frequency specified by the parameters stored in the storage unit 140 .

The output information acquisition unit 132 generates output information indicating the detection result of the sensor 120 based on the signal output by the sensor 120 . Specifically, the output information acquisition unit 132 performs A/D conversion processing and filtering processing on the analog signal output by the sensor 120, and obtains the distance from the sensor 120 to the object and the amplitude of the reflected wave. Identify. For example, the output information acquiring unit 132 identifies the distance from the sensor 120 to the object based on the time from when the sensor 120 transmits the transmission wave to when the sensor 120 receives the reflected wave. Also, the output information acquisition unit 132 identifies the amplitude of the reflected wave received by the sensor 120 . The amplitude of the reflected wave is also referred to as the intensity of the reflected wave and the magnitude of the reflected wave. The output information acquisition unit 132 outputs output information including the specified value indicating the distance and the specified value indicating the amplitude. The output information acquired by the output information acquisition unit 132 is stored in the storage unit 140 as appropriate.

The output information transmission section 133 transmits the output information acquired by the output information acquisition section 132 to the detection section 190 via the communication section 150 . The output information transmission unit 133 may transmit the output information to the detection unit 190 in accordance with a request from the detection unit 190, or may transmit the output information to the detection unit 132 in response to the output information acquisition unit 132 acquiring the output information. 190.

Next, functions of the detection unit 190 will be described with reference to FIG. Functionally, the detection unit 190 includes a parameter transmission unit 1911, a detection instruction unit 1912, an output information acquisition unit 1913, a correction coefficient calculation unit 1914, a correction amount calculation unit 1915, a parameter correction unit 1916, an output An information corrector 1917 and a notification unit 1918 are provided. These functional units are implemented by the functions of the control unit 191 . In other words, these functional units are realized by a computer having a CPU, ROM, RAM, RTC, A/D converter, etc. executing an operation program stored in a ROM or flash memory.

The parameter transmission section 1911 transmits the parameters stored in the storage section 192 to the sensor module 110 via the first communication section 193 . The detection instruction unit 1912 instructs the sensor module 110 to detect an object via the first communication unit 193 . For example, the detection instruction unit 1912 instructs the sensor module 110 to detect an object when the power of the object detection device 100 is turned on or when an instruction is received from the power transmission coil unit 210 or the power supply device 220 . The output information acquisition unit 1913 acquires output information from the sensor module 110 via the first communication unit 193 .

A correction coefficient calculation unit 1914 calculates correction coefficients used for correcting parameters or output information based on the reference information and the reference information. A correction amount calculation unit 1915 calculates a correction amount used for correcting parameters or output information based on the reference information and the reference information. Here, one of a correction coefficient and a correction amount, which is predetermined according to the type of parameter, is used for correction of one parameter. Similarly, to correct one output value included in the output information, one of the correction coefficient and the correction amount, which is predetermined according to the type of output value, is used.

For example, a parameter suitable for correction with a ratio to a reference value is corrected with a correction factor. On the other hand, parameters that are suitable for correcting with the amount of offset from the reference value are corrected with the amount of correction. Also, an output value suitable for correction with a ratio to a reference value is corrected with a correction coefficient. On the other hand, an output value suitable for correction with an offset amount with respect to a reference value is corrected with a correction amount. In this embodiment, the parameter of the amplitude of the transmitted wave is corrected by the correction coefficient, and the output value of the distance from the sensor 120 to the object is corrected by the correction amount.

The parameter correction unit 1916 corrects the parameter for the sensor 120 based on the correction coefficient calculated by the correction coefficient calculation unit 1914 or the correction calculated by the correction amount calculation unit 1915 . The output information correction unit 1917 corrects the output information acquired by the output information acquisition unit 1913 based on the correction coefficient calculated by the correction coefficient calculation unit 1914 or the correction calculated by the correction amount calculation unit 1915 .

The notification unit 1918 executes various notification processes based on the output information acquired by the output information acquisition unit 1913 or the output information corrected by the output information correction unit 1917 . For example, the notification unit 1918 notifies that there is an abnormality when the reference object is not detected continuously for a predetermined number of times. Also, for example, when an object other than a reference object is detected consecutively a predetermined number of times, the notification unit 1918 notifies that there is an object other than the reference object. Note that the notification destinations are the power transmission coil unit 210, the power supply device 220, a terminal device (not shown), and the like.

Next, the processing of the detection unit 190 will be specifically described with reference to FIGS. 8 and 9. FIG. FIG. 8 is a diagram showing reference information stored in the storage unit 192. As shown in FIG. FIG. 9 is a diagram showing output information acquired by the output information acquisition unit 1913. As shown in FIG. As described above, the reference information is the output information obtained from the signal output by the sensor 120 when the reference object is detected in the reference environment and the reference deterioration state. The reference information is set based on the results of experiments, simulations, etc., and is stored in the storage unit 192 in advance. Reference information is information including an output value, and is also called reference data. The output information is information including an output value, and is also called output data.

The reference information shown in FIG. 8 is that the distance from the sensor 120 to the reference object (hereinafter referred to as “detection distance”) is 100 (mm), and the amplitude of the reflected wave to be detected (hereinafter referred to as “ This is information indicating that the detected amplitude") is 1000 (mV). That is, this reference information is information including 100 (mm) as an output value of detection distance and 1000 (mV) as an output value of detection amplitude. This reference information includes an output value of detection distance of 100 (mm) and an output value of detection amplitude of 1000 (mV) in a reference environment and a reference deterioration state. indicates that The detected amplitude, which is the amplitude of the reflected wave, depends on the size of the object, the material of the surface of the object, the angle of the surface of the object, and the like.

The output information shown in FIG. 9 is information indicating that three objects have been detected by three records. A first record whose record number is 1 indicates that an object corresponding to an amplitude of 900 (mV) was detected at a distance of 95 (mm) from the sensor 120 . A second record whose record number is 2 indicates that an object corresponding to an amplitude of 1800 (mV) was detected at a distance of 495 (mm) from the sensor 120 . A third record whose record number is 3 indicates that an object corresponding to an amplitude of 90 (mV) was detected at a distance of 995 (mm) from the sensor 120 .

Here, the detection unit 190 performs a reference object detection process of comparing the output information and predetermined reference information to detect a reference object existing at a predetermined position within the detection range. Specifically, the detection unit 190 determines whether or not the output information includes a reference object corresponding record, which is a record including an output value similar to the output value included in the reference information. If the detection unit 190 determines that the reference object corresponding record is included in the output information, it determines that the reference object is detected. On the other hand, if the detection unit 190 determines that the reference object corresponding record is not included in the output information, it determines that the reference object is not detected.

It should be noted that the method of determining whether or not a specific record is a reference object record can be adjusted as appropriate. For example, for all types of output values, if the difference between the output value included in the reference information and the output value included in the specific record is less than or equal to a predetermined value, the specific record is the reference object record. can be determined. Alternatively, for all types of output values, if the ratio of the output value included in the specific record to the output value included in the reference information is within a predetermined ratio range, the specific record is a reference-corresponding record can be determined to exist.

For example, it is assumed that the threshold for the difference in detection distance is 10 (mm) and the range of the detection amplitude ratio is 0.8 to 1.2. When the reference information includes 100 (mm) as the detection distance and 1000 (mV) as the detection amplitude, the detection distance within the range from 90 (mm) to 110 (mm) and the detection distance from 800 (mV) to 1200 ( mV) are reference-corresponding records. A record with a record number of 1 is a record corresponding to a reference object because it includes a detection distance of 95 (mm) and a detection amplitude of 900 (mV).

That is, the output information shown in FIG. 9 indicates that one reference object and two objects other than the reference objects have been detected. An object other than the reference object is appropriately called a detection object. Information indicating a reference object among the output information is appropriately referred to as reference object information. Information indicating the detection target among the output information is appropriately referred to as detection target information.

When the reference object is detected, the detection unit 190 corrects at least one of the output information and the parameter for the sensor 120 based on the reference information indicating the reference object in the output information and the reference information. Execute correction processing. For example, the detection unit 190 corrects the parameter when the output information can be indirectly adjusted by correcting the parameter. On the other hand, the detection unit 190 corrects the output information when the output information cannot be indirectly adjusted by correcting the parameters. In this embodiment, the detection unit 190 corrects the output information and the parameters based on the reference information and the reference information in the correction process.

In this embodiment, the parameters for sensor 120 include first parameters and second parameters, and the output information includes first output values and second output values. The first parameter is a parameter that affects the first output value. The second parameter may be a parameter that affects the first output value and the second output value, or may be a parameter that does not affect the first output value and the second output value. The first output value is an output value that varies due to correction of the first parameter. The second output value is an output value that does not change due to the correction of the first parameter.

Here, in the correction process, the detection unit 190 corrects the second output value of the output information and the first parameter of the parameters based on the reference information and the reference information. The first parameter is the amplitude of the transmitted wave, the second parameter is the frequency of the transmitted wave, the first output value is the detected amplitude, and the second output value is the detected distance. That is, the detection unit 190 corrects the detected distance among the output information and the amplitude of the transmission wave among the parameters.

When the amplitude of the transmission wave emitted by the sensor 120 changes, the detected amplitude included in the acquired output information changes. On the other hand, even if the amplitude and frequency of the transmission wave emitted by the sensor 120 are changed, the detected distance included in the acquired output information does not change. That is, the detection amplitude is adjustable by parameter correction, and the detection distance is not adjustable by parameter correction. The detected amplitude is then adjusted by correcting the parameters, and the detected distance is adjusted by correcting the output information.

For example, the detected amplitude included in the reference information is 1000 (mV), and the detected amplitude included in the reference information is 900 (mV). That is, the current situation is a situation in which the detected amplitude is 900/1000=0.9 times as large as the reference situation. Therefore, the amplitude of the transmission wave is corrected so that the detected amplitude can be detected with the same amplitude as in the reference situation. For example, the amplitude of the transmitted wave is corrected to 10/9 times the current amplitude. By correcting the amplitude of the transmitted wave, the detected amplitude contained in the output information is adjusted to an appropriate value.

After correcting the amplitude of the transmitted wave, the first record containing 900×10/9=1000 (mV) as the detected amplitude, the second record containing 1800×10/9=2000 (mV) as the detected amplitude, and the detected amplitude It can be expected that the output information is adjusted to include the third record containing 90×10/9=100 (mV) as . Note that information indicating the correspondence relationship between the parameter change amount and the output value change amount included in the output information is stored in the storage unit 192, for example. For example, the storage unit 192 stores information indicating the correspondence relationship between the amount of change in the amplitude of the transmission wave and the amount of change in the predicted amplitude of the detected amplitude.

The detection distance included in the reference information is 100 (mm), and the detection distance included in the reference information is 95 (mm). That is, the current situation is a situation in which the detection distance is detected at a length shorter by 100−95=5 (mm) than the reference situation. Therefore, the detection distance included in the output information is corrected in order to make the detection distance approximately the same length as the reference situation. For example, the detection distance included in the output information is increased by 5 (mm). After correction of the detection distance, the output information includes the first record including 95+5=100 (mm) as the detection distance, the second record including 495+5=500 (mm) as the detection distance, and the 995+5=1000 (mm) as the detection distance. ) and a third record containing

Thus, in the correction process, the detection unit 190 corrects at least one of the output information and the parameter based on the correction coefficient or correction amount based on the reference information and the reference information. In the above example, the correction coefficient is 10/9 and the correction amount is 5 (mm).

Here, the detection unit 190 repeatedly executes the process of determining the presence or absence of an object in the first cycle. Then, when a reference object is detected in the reference object detection process, the detection unit 190 updates the correction coefficient or the correction amount every second cycle longer than the first cycle. That is, in the present embodiment, the period of updating the correction coefficient or the amount of correction is longer than the period of executing the process of determining whether or not there is an object.

Next, object detection processing executed by the object detection device 100 will be described with reference to FIG. 10 . The object detection process is repeatedly executed, for example, from electric vehicle 700 approaching power transmission device 200 until power transmission ends. Object detection device 100 receives notification from power transmission device 200 that electric vehicle 700 has approached power transmission device 200, that power transmission has started, that power transmission has ended, and the like.

First, the detection unit 190 included in the object detection device 100 executes detection start processing (step S101). Specifically, first, the detection unit 190 transmits the initial values of the parameters stored in the storage unit 192 to the sensor module 110 . The detection unit 190 then instructs the sensor module 110 to start detecting an object. After that, the sensor module 110 repeatedly executes the process of detecting an object in the first cycle.

In the process of detecting an object, first, the control unit 130 supplies the sensor 120 with a voltage pulse for causing the sensor 120 to transmit a transmission wave having an amplitude and frequency corresponding to the initial values of the parameters. On the other hand, the sensor 120 transmits a transmission wave corresponding to this voltage pulse, and supplies a signal corresponding to a reflected wave of this transmission wave to the control section 130 . Control unit 130 generates output information based on the signal supplied from sensor 120 . For example, the control unit 130 identifies the distance from the sensor 120 to the object based on the time from transmission of the transmission wave to reception of the reflected wave. Also, the control unit 130 identifies the amplitude of the received reflected wave. Control unit 130 generates output information including the detected distance, which is the specified distance, and the detected amplitude, which is the specified amplitude.

After completing the process of step S101, the detection unit 190 determines whether or not the current time is the timing that comes every first cycle (step S102). The first cycle is a cycle in which the detection unit 190 acquires output information from the sensor 120, and is a cycle in which the detection unit 190 determines whether or not there is a detection target. In this embodiment, the sensor module 110 automatically acquires output information every first cycle. Therefore, in step S102, the detection unit 190 may determine whether the sensor module 110 has acquired new output information. If the detection unit 190 determines that the current time does not come every first cycle (step S102: NO), the process returns to step S102.

On the other hand, when the detection unit 190 determines that the current time is the timing that comes every first cycle (step S102: YES), it acquires output information (step S103). That is, the detection unit 190 acquires output information generated by the sensor module 110 .

After completing the process of step S103, the detection unit 190 determines whether or not there is a reference object within the detection range (step S104). That is, the detection unit 190 determines whether or not the reference object corresponding record is included in the output information. If the detection unit 190 determines that there is no reference object within the detection range (step S104: NO), it determines whether or not it has determined that there is no reference object continuously for a specified number of times (step S105). If the detection unit 190 determines that there is no reference object consecutively for the prescribed number of times (step S105: YES), it notifies that there is an abnormality (step S106).

For example, the detection unit 190 notifies that there is an abnormality in the power transmission coil unit 210, the power supply device 220, the terminal device, or the like. Note that the power transmission coil unit 210, the power supply device 220, the terminal device, and the like execute appropriate processing when receiving this notification. For example, upon receiving this notification, the power supply device 220 may assume that there is some kind of abnormality and stop power transmission.

If the detection unit 190 determines that there is a reference object within the detection range (step S104: YES), it excludes the reference object information from the output information (step S107). The output information from which the reference object information is excluded is the detection target object information. After completing the process of step S107, the detection unit 190 saves the reference information (step S108). For example, the detection unit 190 stores the reference object information in the storage unit 192 .

If the detection unit 190 does not determine that there is no reference object continuously for the specified number of times (step S105: NO), or if the process of step S106 or step S108 is completed, the update process is executed (step S109 ). The update process will be described in detail with reference to the flowchart shown in FIG.

First, the detection unit 190 determines whether or not the timing arrives every second cycle (step S201). The second cycle is a cycle for updating the correction coefficient and the correction amount, and is a cycle longer than the first cycle. The second period is, for example, about 100 times the first period. For example, if the first period is 10 msec, the second period is 1 sec. When the detection unit 190 determines that the timing comes every second period (step S201: YES), it determines whether or not the reference object has been detected in the most recent second period (step S202). For example, when at least one piece of reference object information is stored in the storage unit 192, the detection unit 190 determines that the reference object was detected in the most recent second period.

If the detection unit 190 determines that the reference object has been detected in the most recent second period (step S202: YES), it calculates a correction coefficient and a correction amount from the reference object information and the reference information (step S203). For example, the detection unit 190 calculates the correction coefficient based on the ratio of the detected amplitude included in the reference information to the detected amplitude included in the reference object information. Further, the detection unit 190 calculates the difference between the detection distance included in the reference object information and the detection distance included in the reference information as a correction amount. In addition, when a plurality of reference object information is stored in the most recent second cycle, the correction coefficient or correction amount may be calculated based on the latest output value, or the average value of the plurality of output values may be corrected. A coefficient or correction amount may be calculated.

After completing the process of step S203, the detection unit 190 updates the correction coefficient and the correction amount (step S204). Note that the correction coefficient and the correction amount are stored in the storage unit 192, for example. After completing the process of step S204, the detection unit 190 corrects the parameter using the correction coefficient or the correction amount (step S205). For example, the detection unit 190 sets, in the sensor module 110, a value obtained by multiplying the amplitude of the transmission wave currently set in the sensor module 110 by a correction coefficient as the new amplitude of the transmission wave.

After completing the process of step S205, the detection unit 190 deletes the reference information stored in the storage unit 192 (step S206). If the detection unit 190 determines that the timing does not come every second period (step S201: NO), if it determines that the reference object is not detected in the most recent second period (step S202: NO), or , when the processing of step S206 is completed, the update processing is completed.

After completing the update process in step S109, the detection unit 190 corrects the output information using the correction coefficient or the correction amount (step S110). Specifically, the detection unit 190 corrects the detection distance included in the output information, that is, the detection distance included in the object information, using the correction amount of the detection distance. After completing the update process in step S110, the detection unit 190 executes an object presence/absence determination process (step S111).

Specifically, the detection unit 190 determines the presence or absence of the detection target based on the detection distance and the detection amplitude included in the corrected target object information, which is the corrected output information. For example, assume that the minimum amplitude detected as a detection target is 500 (mV) and the farthest distance of the detection target is 2000 (mm). In this case, a record including a detected amplitude of less than 500 (mV) and a record including a detected distance of over 2000 (mm) are not regarded as records indicating a detection target.

For example, the corrected object information includes a second record including 500 (mm) as the detection distance and 2000 (mV) as the detection amplitude, and a second record including 1000 (mm) as the detection distance and 100 (mV) as the detection amplitude. ) and a third record containing In this case, the second record is regarded as the record indicating the detection object, but the third record is not regarded as the record indicating the detection object because the detected amplitude is smaller than the lowest amplitude. Therefore, the detection unit 190 determines that there is one detection target indicated by the second record.

Note that the detection unit 190 can perform various types of processing based on the detection result of the detection target. For example, when the detection unit 190 determines that there is a detection target continuously for a specified number of times, the detection unit 190 can notify that the detection target has been detected. The notification destination is the power transmission coil unit 210, the power supply device 220, a terminal device (not shown), or the like. After completing the update process in step S111, the detection unit 190 returns the process to step S102.

In the present embodiment, when a reference object is detected, correction processing is performed to correct at least one of the output information and the parameters for the sensor based on the reference object information and the reference object information. Therefore, according to this embodiment, an object can be detected with high accuracy during wireless power transmission.

Also, in the present embodiment, the output information and parameters are corrected. Therefore, according to the present embodiment, the information used for determining the presence or absence of an object is efficiently adjusted.

In particular, in the present embodiment, of the first output value that varies due to the correction of the first parameter and the second output value that does not vary due to the correction of the first parameter, the second output value and the first parameter are corrected. . Therefore, according to the present embodiment, all output values included in the output information can be adjusted without correcting the output values included in the output information as much as possible.

Further, in the present embodiment, the process of determining the presence or absence of an object is repeatedly executed in the first cycle, and when the reference object is detected, the correction coefficient or the correction amount is updated every second cycle longer than the first cycle. be done. According to this embodiment, output information or parameter correction can be realized with a small processing load.

Further, in this embodiment, if the reference object is not detected for a predetermined number of times in succession, it is notified that there is an abnormality. Therefore, according to the present embodiment, it is possible to prevent the fact that the accuracy of the object detection result is questionable from being overlooked.

Also, in this embodiment, the reference is at least part of at least one other sensor module 110 that exists within the detection range of the sensor 120 that each sensor module 110 has. Therefore, according to the present embodiment, it is not necessary to prepare an unnecessary object as a reference object for the object detection apparatus 100, so an increase in the number of parts and an increase in cost can be suppressed.

Further, in the present embodiment, the reference object is an object that remains stationary while power transmission coil unit 210 transmits power. Therefore, according to the present embodiment, the information used for determining the presence or absence of an object is adjusted with high accuracy.

Further, in the present embodiment, the reference object is a part of the object that constitutes power transmission device 200 . Therefore, according to the present embodiment, it is not necessary to prepare an unnecessary object for the power transmission device 200 as a reference object, thereby suppressing an increase in the number of parts and an increase in cost.

(Embodiment 2)
Embodiment 1 has described an example in which a plurality of sensor modules 110 and power transmission coil units 210 are separately arranged. In this embodiment, an example in which a plurality of sensor modules 110 are housed in housing 214 of power transmission coil unit 210 will be described. Note that the description of the same configuration and processing as in the first embodiment is omitted or simplified.

FIG. 12 shows a layout diagram of the sensor module 110 according to this embodiment. In this embodiment, four sensor modules 110 are incorporated inside housing 214 of power transmission coil unit 210 . Specifically, the four sensor modules 110 are housed in the four corners of a housing 214 that is substantially rectangular in plan view. In this embodiment, the housing 214 serves as a housing for the four sensor modules 110 , and the four sensor modules 110 do not have the housing 160 . An opening is provided in a portion of the housing 214 that receives the transmission wave emitted by the sensor 120 .

Further, in this embodiment, the four sensor modules 110 are arranged so that the detection range 119 of each sensor 120 includes a part of the housing 214 . In the example shown in FIG. 12, the detection range 119A of the sensor 120 included in the sensor module 110A includes the portion 214B of the housing 214. As shown in FIG. A portion 214C of the housing 214 is included in the detection range 119B of the sensor 120 included in the sensor module 110B. A detection range 119C of the sensor 120 included in the sensor module 110C includes a portion 214D of the housing 214. As shown in FIG. A detection range 119D of the sensor 120 included in the sensor module 110D includes a portion 214A of the housing 214. As shown in FIG. In this embodiment, portions 214A, 214B, 214C, and 214D are references.

In the present embodiment, multiple sensor modules 110 are housed in housing 214 of power transmission coil unit 210 . Therefore, according to the present embodiment, the trouble of arranging the plurality of sensor modules 110 is reduced.

Further, in the present embodiment, the reference object is part of the object that constitutes power transmission coil unit 210 . Therefore, according to the present embodiment, it is not necessary to prepare an unnecessary object for the power transmission device 200 as a reference object, thereby suppressing an increase in the number of parts and an increase in cost.

Further, in the present embodiment, the reference object is an object that remains stationary while power transmission coil unit 210 transmits power. Therefore, according to the present embodiment, the information used for determining the presence or absence of an object is adjusted with high accuracy.

(Embodiment 3)
In the first embodiment, an example has been described in which the reference is at least part of at least one other sensor module 110 that exists within the detection range of the sensor 120 that each sensor module 110 has. In this embodiment, an example in which the reference object is part of the housing 224 of the power supply device 220 will be described. Note that the description of the same configuration and processing as in the first and second embodiments will be omitted or simplified.

FIG. 13 shows a layout diagram of the sensor module 110 according to this embodiment. In this embodiment, four sensor modules 110 are provided near the four corners of housing 224 of power supply device 220, which is substantially rectangular in plan view. In this embodiment, the four sensor modules 110 are arranged such that the detection range 119 of each sensor 120 includes a portion of the housing 224 .

In the example shown in FIG. 13, a portion 224A of the housing 224 is included in the detection range 119A of the sensor 120 provided in the sensor module 110A. A portion 224B of the housing 224 is included in the detection range 119B of the sensor 120 included in the sensor module 110B. A detection range 119C of the sensor 120 included in the sensor module 110C includes a portion 224C of the housing 224 . A detection range 119D of the sensor 120 included in the sensor module 110D includes a portion 224D of the housing 224. As shown in FIG. In this embodiment, portions 224A, 224B, 224C, and 224D are references.

In the present embodiment, the reference object is part of an object that constitutes power transmission device 200 . Therefore, according to the present embodiment, it is not necessary to prepare an unnecessary object for the power transmission device 200 as a reference object, thereby suppressing an increase in the number of parts and an increase in cost.

Further, in the present embodiment, the reference object is an object that remains stationary while power transmission coil unit 210 transmits power. Therefore, according to the present embodiment, the information used for determining the presence or absence of an object is adjusted with high accuracy.

(Embodiment 4)
In Embodiment 1, an example has been described in which the second cycle in which the correction coefficient or correction amount is updated is longer than the first cycle in which the presence or absence of the detection target is determined. In this embodiment, an example in which the first period and the second period are the same will be described. Note that the description of the same configuration and processing as in Embodiments 1-3 will be omitted or simplified.

In this embodiment, instead of the update process shown in FIG. 11, the update process shown in FIG. 14 is executed. First, the detection unit 190 determines whether or not a reference object is detected (step S301). For example, when reference object information is stored in the storage unit 192, the detection unit 190 determines that a reference object has been detected. When the detection unit 190 determines that the reference object is detected (step S301: YES), it calculates a correction coefficient and a correction amount from the reference object information and the reference information (step S302).

After completing the process of step S302, the detection unit 190 updates the correction coefficient and the correction amount (step S303). After completing the process of step S303, the detection unit 190 corrects the parameter using the correction coefficient or the correction amount (step S304). After completing the process of step S304, the detection unit 190 deletes the reference information stored in the storage unit 192 (step S305). When the detection unit 190 determines that no reference object is detected (step S301: NO), or when the processing of step S305 is completed, the update processing is completed.

In this embodiment, the process of determining the presence or absence of an object is repeatedly executed in the first period, the reference object detection process is executed in each first period, and the correction process is executed when the reference object is detected. According to this embodiment, when the output information changes according to a change in situation, the output information or parameters are corrected promptly.

(Modification)
Although the embodiments of the present disclosure have been described above, various modifications and applications are possible in carrying out the present disclosure. In the present disclosure, any part of the configurations, functions, and operations described in the above embodiments may be adopted. Further, in addition to the configurations, functions, and operations described above, additional configurations, functions, and operations may be employed in the present disclosure. Moreover, the above embodiments can be freely combined as appropriate. Also, the number of components described in the above embodiment can be adjusted as appropriate. Further, it goes without saying that materials, sizes, electrical characteristics, etc. that can be employed in the present disclosure are not limited to those shown in the above embodiments.

In Embodiment 1, an example in which the number of sensors is four has been described. The number of sensors may be three or less, or may be five or more. Moreover, in Embodiment 1, an example in which an ultrasonic sensor is adopted as the sensor 120 used for detecting an object has been described. Various sensors can be employed as the sensor 120 . For example, as the sensor 120, a millimeter wave sensor, an X-band sensor, an infrared sensor, or a visible light sensor can be used.

In the first embodiment, an example has been described in which the range of detection distance and detection amplitude for determining that there is an object to be detected is fixed. The range of the detection distance and the detection amplitude for determining that there is a detection target may be adjusted according to the magnitude of power transmitted from the power transmission device 200 to the power reception device 300, for example.

Embodiment 1 explained an example in which the output information includes the detected distance and the detected amplitude as output values. The output value included in the output information may be another output value. For example, the output value included in the output information may be the time from when the sensor 120 transmits a transmission wave to when it receives a reflected wave, the size of an object, the direction in which the object is detected, and the like. Further, in Embodiment 1, an example was described in which the parameters for the sensor 120 include the amplitude of the transmission wave and the frequency of the transmission wave. The parameters for sensor 120 may include other parameters.

Embodiment 1 has described an example in which both the output information and the parameters are corrected. At least one of the output information and the parameters should be corrected. For example, only output information may be corrected, or only parameters may be corrected.

In the first embodiment, an example has been described in which the detected distance is corrected by the correction amount and the amplitude of the transmission wave is corrected by the correction coefficient. Whether the output information or the parameter is corrected by the correction amount or the correction coefficient can be appropriately adjusted. For example, the detection distance may be corrected with a correction coefficient, and the amplitude of the transmission wave may be corrected with a correction amount. Further, it is possible to appropriately adjust which of the output information and the parameters is to be corrected. For example, instead of correcting the parameter of the amplitude of the transmitted wave, the detected amplitude included in the output information may be corrected.

By applying an operation program that defines the operation of the object detection device 100 according to the present disclosure to a computer such as an existing personal computer or an information terminal device, the computer may function as the object detection device 100 according to the present disclosure. It is possible. Any method of distributing such programs may be used. For example, a CD-ROM (Compact Disk ROM), a DVD (Digital Versatile Disk), an MO (Magneto Optical Disk), or a computer-readable recording medium such as a memory card may be used. It may be stored in a medium and distributed, or may be distributed via a communication network such as the Internet.

This disclosure is capable of various embodiments and modifications without departing from the broader spirit and scope of this disclosure. In addition, the embodiments described above are for explaining the present disclosure, and do not limit the scope of the present disclosure. That is, the scope of the present disclosure is indicated by the claims rather than the embodiments. Various modifications made within the scope of the claims and within the scope of equivalent disclosure are considered to be within the scope of the present disclosure.

100 object detection devices 110, 110A, 110B, 110C, 110D sensor modules 119, 119A, 119B, 119C, 119D detection range 120 sensors 130, 191 control unit 131 drive units 132, 1913 output information acquisition unit 133 output information transmission unit 140, 192 storage unit 150 communication unit 160, 160A, 160B, 160C, 160D, 214, 224 housing 161 opening 170 detection board 180 cable 190 detection unit 193 first communication unit 194 second communication unit 200 power transmission device 210 power transmission coil unit 211 Power transmitting coils 212, 312 Magnetic plates 213, 313 Coil shaft 220 Power supply device 300 Power receiving device 310 Power receiving coil unit 311 Power receiving coil 320 Rectification circuit 400 Commercial power supply 500 Storage battery 700 Electric vehicle 1000 Power transmission system 1911 Parameter transmission unit 1912 Detection instruction unit 1914 correction coefficient calculation unit 1915 correction amount calculation unit 1916 parameter correction unit 1917 output information correction unit 1918 notification unit

Claims (13)

An object detection device that detects an object existing in a detection range,
a sensor module having a sensor and a control unit that controls the sensor and generates output information based on a signal output by the sensor;
a detection unit that determines the presence or absence of the object based on the output information,
The detection unit performs a reference object detection process of comparing the output information with predetermined reference information to detect a reference object existing at a predetermined position within the detection range, If detected, a correction process is performed to correct at least one of the output information and the parameter for the sensor based on the reference information indicating the reference object in the output information and the reference information. do,
Object detection device. wherein, in the correction process, the detection unit corrects the output information and the parameter based on the reference object information and the reference information;
The object detection device according to claim 1. The parameters include a first parameter,
the output information includes a first output value that varies due to correction of the first parameter and a second output value that does not vary due to correction of the first parameter;
In the correction process, the detection unit corrects the second output value of the output information and the first parameter of the parameters based on the reference object information and the reference information.
The object detection device according to claim 2. The detection unit repeatedly executes the process of determining the presence or absence of the object in a first period, executes the reference object detection process in each of the first periods, and executes the correction process when the reference object is detected. Run,
The object detection device according to any one of claims 1 to 3. wherein, in the correction process, the detection unit corrects at least one of the output information and the parameter based on a correction coefficient or a correction amount based on the reference information and the reference information;
The detection unit repeatedly executes the process of determining the presence or absence of the object in a first period, and when the reference object is detected in the reference object detection process, the detection unit performs the updating the correction factor or the correction amount;
The object detection device according to any one of claims 1 to 3. The detection unit includes a notification unit that notifies that there is an abnormality when the reference object is not detected continuously for a predetermined number of times in the reference object detection process.
The object detection device according to claim 4 or 5. comprising a plurality of the sensor modules,
the plurality of sensor modules are arranged such that the sensor detection range of each sensor module includes at least a portion of at least one other sensor module;
The reference is at least part of the at least one other sensor module that is within the detection range of the sensor that each sensor module has.
The object detection device according to any one of claims 1 to 6. an object detection device according to claim 7;
a power transmission coil unit that includes a power transmission coil and wirelessly transmits power to the power receiving device;
The reference object is an object that is stationary while the transmitting coil unit transmits power.
transmission device. The power transmission coil unit has a housing that houses the power transmission coil,
The plurality of sensor modules are housed in the housing of the power transmission coil unit,
The power transmission device according to claim 8 . an object detection device according to any one of claims 1 to 6;
a power transmission coil unit that includes a power transmission coil and wirelessly transmits power to the power receiving device;
The reference object is an object that is stationary while the transmitting coil unit transmits power.
transmission device. The reference object is a part of an object that constitutes the power transmission device,
The power transmission device according to claim 10. The reference object is a part of an object that constitutes the power transmission coil unit,
The power transmission device according to claim 10 or 11. the power transmission device according to any one of claims 8 to 12;
a power receiving device mounted on a mobile body and receiving power from the power transmitting device;
power transmission system.

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